1. Field of the Invention
The present invention relates to hydrogenated starch hydrolysate compositions.
2. Description of the Prior art
Polyols (polyalcohols), such as hydrogenated starch hydrolysates, maltitol, isomaltitol, maltotriitol, or combinations thereof, are commonly used as artificial sweeteners in food confectionary products, such as hard candies and chewing gum. These materials are highly hygroscopic which makes them essentially non-dehydratable by conventional methods. Product applications, however, are often dependent on the availability of a non-hygroscopic free-flowing powder. Various drying techniques have been attempted on the above-mentioned polyols, such as conventional spray-drying and freeze-drying. However, these drying techniques fail to produce a product that is stable to temperature and moisture. Spray drying techniques are unsatisfactory because of atomizer blockage and formation of glassy deposits. Other more sophisticated drying techniques, such as freeze-drying and foam-mat drying, are uneconomical.
Boiled sweets, commonly called hard sweets or hard boiled candies, are solid and essentially amorphous confectionary products. They are obtained by extensive dehydration of carbohydrate syrups. While the principal market for boiled sweets currently consists of sugar products prepared from non-hydrogenated carbohydrate syrups, there exists a substantial market for sugar-free or polyol-containing essentially amorphous boiled sweets, which are obtained using hydrogenated carbohydrate (e.g., saccharides) syrups. Sugarless boiled sweets are attractive to the consumer because they do not promote tooth decay and are less caloric than conventional sucrose-containing boiled sweets, while presenting similar organoleptic characteristics.
Generally, sugar-free hard boiled sweets are manufactured by boiling mixtures of polyols dissolved into water. Often, polyols in a powdered form are added to a maltitol syrup. Conventional powdered polyols include maltitol, mannitol, erythritol, and isomalt. Isomalt can also be used alone after dissolution into water. The mixtures of polyols are usually boiled at 150-200xc2x0 C., under reduced pressure (e.g., about 16-25 inches of mercury), in order to evaporate most of the water (i.e., bring the water content of the mixture to a value which is normally less than 6.0%, and in some cases, less than 3.0% by weight water). The molten mass which is obtained is then cooled and cast or deposited into moulds or formed on rolls or by extrusion after the addition of various ingredients, such as flavorants, colorants, intense sweeteners, fillers, acids, plant extracts, vitamins, pharmaceutical active ingredients, and the like. After returning to room temperature, the products have a texture and an appearance similar to that of glass.
Sugar-free boiled sweets must be stable over time. They must have an adequate shelf-life which varies as little as possible from the time when they are manufactured up to the time when they are consumed, so as to provide products which are attractive and pleasant in the mouth. Sugar-free boiled sweets, unfortunately, are not stable products from a thermodynamic point of view. The extent of the instability depends essentially upon the composition and the conditions under which the sugarless boiled sweets are preserved. One of the most common major problems is that sugar-free boiled sweets may become sticky during storage. Once wrapped, the stickiness makes it difficult or impossible to remove the wrapping materials before they are consumed. In addition, the sugarless boiled sweets may become flowable and lose their shape.
This problematic variation towards a sticky and syrupy state can be explained by surface phenomena and depth phenomena. The origin of surface phenomena is in the hygroscopic nature of boiled sweets. It is known that boiled sweets, which are essentially anhydrous products, have very low equilibrium relative humidities, substantially lower than the ambient relative humidities commonly found under normal storage conditions. This explains why an uptake of water necessarily occurs at the surface of the sweets as soon as they are exposed to air. When this water uptake is sufficiently high, it tends to liquify the surface of the sweets, which takes on the characteristics of a syrup and makes them sticky. The higher the water content of the boiled sweets, the quicker this phenomena occurs.
The depth phenomena have a thermal origin. When a boiled sweet is exposed to a temperature that is above the glass transition temperature (Tg) of the boiled sweet, the boiled sweet will become deformable and can even melt. To avoid the negative aspects of the depth phenomena, it is generally preferred that the storage temperature is below the glass transition temperature (Tg) of the boiled sweet. This preference is known in the art and is discussed in an article entitled xe2x80x9cLa transition vitreuse: incidences en technologic alimentairexe2x80x9d [Glass transition: incidents in food technology] by M. Le Meste and D. Simalos, published in I.A.A. of January/February, 1990, which is hereby incorporated by reference. The glass transition temperature is the temperature at which, upon heating, a glassy and solid boiled sweet softens and eventually becomes a syrupy liquid. This temperature is normally measured by differential scanning calorimetry (DSC). However, it is also understood that a boiled sweet may be subject to a deformation, or even to a complete flow, when its storage temperature significantly exceeds its glass transition temperature. In such a case, the initially dry product becomes sticky. Furthermore, the higher the water content of the boiled sweet in question, the lower the glass transition temperature of the boiled sweet and the greater the risk of stickiness, deformation or flowing during the storage of the boiled sweet.
In order to avoid unstable boiled sweets becoming sticky products over time, it has been generally necessary to lower their content of water. While, recent advances in the art have provided somewhat stable sugar-free boiled sweets having greater than 3% water contents, there still exists a need to provide a sugarless sweet which is more stable to temperature and moisture.
U.S. Pat. No. 5,629,042 to Serpelloni et al., which is hereby incorporated by reference, discloses a sugarless boiled sweet containing a water crystallizable polyol and carbohydrates (e.g., saccharides). The boiled sweet has a water content greater than 3% and a glass transition temperature greater than or equal to 38xc2x0 C., the glass transition temperature being measured at a water content of about 3.2%.
U.S. Pat. No. 4,248,895 to Stroz et al., which is hereby incorporated by reference, shows hydrogenated starch hydrolysates having total solids contents of about 72 to 80 wt.-%. Based on the dry hydrogenated starch hydrolysates, the total solids contents consist of about 4 to 20 wt.-% sorbitol (hydrogenated monosaccharide), 20 to 65 wt.-% hydrogenated dissaccharides (e.g., maltitol), 15 to 45 wt.-% tri- to hepta-hydrogenated oligosaccharides, and 10 to 35 wt. % hydrogenated polysaccharides higher than hepta.
U.S. Pat. No. 4,445,938 to Verwaerde et al., which is hereby incorporated by reference, discloses dry hydrogenated starch hydrolysates consisting of, based on total solids content, less than 14 wt.-% of hydrogenated monosaccharides (e.g., sorbitol), less than 35 wt.-% of hydrogenated dissaccharides (e.g., maltitol), 12 to 18 wt.-% of hydrogenated trisaccharides, between 42 and 70 wt.-% of hydrogenated quat- to deca-oligosaccharides, and less than 32 wt.-% of hydrogenated polysaccharides greater than deca. The Verwaerde composition provides a more stable hydrogenated starch hydrolysate than one which has 15.5 or 30.0 wt.-% of hydrogenated quat- to deca-oligosaccharides.
When the hydrogenated starch hydrolysate syrups that are presently on the market (e.g., HYSTAR 3375 from Lonza and RA 1000 from Roquette) are used to produce hard boiled candies or sweets, the candies or sweets are relatively unstable at high storage temperatures and/or high water contents, which can result in a sticky candy or sweet as explained above. Accordingly, the present invention satisfies a long-felt need by providing a new hydrogenated starch hydrolysate which can be used to prepare hard boiled candies that are stable at high temperatures and high water contents and absorb little moisture in humid conditions. The various kinds of hydrogenated mono-, di-, oligo- and poly-saccharides are characterized by the degree of polymerization (xe2x80x9cDPxe2x80x9d) after hydrogenation. Hydrogenated monosaccharides have a DP=1. Hydrogenated dissaccharides have a DP=2. Hydrogenated tri-, quat-, penta-, hexa-, hepta-, octa-, nona-, and deca-saccharides have DPs of 3, 4, 5, 6, 7, 8, 9 and 10, respectively. Hydrogenated undeca- and greater saccharides have DPs of 11 or greater. The DP may be determined by routine HPLC analysis.
Accordingly, it is an object of the present invention to provide a stable hydrogenated starch hydrolysate, which is generally in syrup form (i.e., an aqueous solution) but can be in the form of a dry powder (e.g., by spray drying the syrup).
It is a further object of the present invention to provide a hydrogenated starch hydrolysate syrup which can be used to prepare hard boiled candies that are stable at high temperatures and high water contents.
It is still another object of the present invention to provide a stable hydrogenated starch hydrolysate which can be used to prepare hard boiled candies that absorb little water under humid conditions.
It is yet a further object of the present invention to provide a stable hydrogenated starch hydrolysate syrup which can be used to make confectionary products, especially sugarless hard boiled sweets or candies.
It is another object of the present invention to provide a stable hydrogenated starch hydrolysate having a high glass transition temperature.
It is still another object of the present invention to provide a stable hydrogenated starch hydrolysate syrup which has a reduced caloric content, good physical properties, good anticrystallizing power, and a viscosity which is not too high (e.g., about 11,000-16,500 cps).
These and other objects and advantages of the present invention can be appreciated by referring to the following description and claims or may be learned by the practice of this invention.
The present invention relates to hydrogenated starch hydrolysates which have a content of hydrogenated monosaccharides (DP=1) of less than 8 wt.-%, a content of hydrogenated dissaccharides (DP=2) of less than 41 wt.-%, a content of hydrogenated trisaccharides (DP=3) of less than 15 wt.-%, a content of hydrogenated oligosaccarides of hydrogenated quat- to deca-oligosaccharides (DP=4 to 10) of less than 30 wt.-%, and a content of hydrogenated polysaccharides of greater than hydrogenated decasaccharides (DPxe2x89xa711) of about 14 to about 38 wt.-%.